Data Communication Method And Apparatus

ABSTRACT

The invention provides a data communication method, including: sending, by the first electrical node, request information to an electrical node, where the request information is used to request an expected data volume quota of a first VOQ, and the first VOQ stores at least one first data packet to be sent to the electrical node; receiving response information, where the response information includes a target data volume quota; and sending the at least one first data packet to the electrical node via the at least one optical node based on the target data volume quota.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of International Application No.PCT/CN2018083592, filed on Apr. 18, 2018, the disclosure of which ishereby incorporated by reference in its entirety.

TECHNICAL FIELD

Embodiments of this application relate to the field of communicationstechnologies, and in particular, to a data communication method andapparatus.

BACKGROUND

A data center network (Dater Center Network, DCN) generally uses afat-tree networking mode to provide a fully connected network for a massof servers (Server) in a data center and exchange data between differentservers. With a requirement for higher bandwidth in the data center, ahybrid networking mode of using optical switching to replace someswitching nodes at a core (Core) layer in fat-tree networking isproposed in the industry to reduce power consumption and increasebandwidth.

For example, as shown in FIG. 1, a network includes an access layer(which may also be referred to as a TOR layer) and a core layer. Ahybrid networking mode of electrical switching (for an E node) andoptical switching (for an O node) is used at the core layer of thenetwork. In a data traffic exchange process, a burst small flow isusually transmitted through electrical switching at the core layer, anda continuous and stable large flow is transmitted through opticalswitching at the core layer. The small flow refers to a flow with shortduration and a relatively small data volume, and the large flow refersto a flow with relatively long duration and a relatively large datavolume. In this way, through electrical switching, burst traffic that isto be transmitted from a plurality of source nodes at the access layerto one destination node may be buffered in a local buffer, to avoid apacket loss.

However, in the foregoing method, a quite large buffer is needed for anode at the access layer to distinguish between the large flow and thesmall flow. Further, this may cause an extra latency. In addition, ascheduling process of optical switching is complex, and onlycoarse-grained scheduling can be implemented. Therefore, it is difficultto ensure an end-to-end quality of service (Quality of Service, QoS)requirement.

SUMMARY

Embodiments of this application provide a data communication method andapparatus, to reduce a latency in a data communication process andensure an end-to-end QoS requirement.

To achieve the foregoing objectives, the following technical solutionsare used in the embodiments of this application.

According to a first aspect, a data communication method is provided andis applied to a data communication network including at least twoswitching layers, where the at least two switching layers include afirst layer and a second layer, the first layer includes a firstelectrical node and a second electrical node, the second layer includesat least one optical node and a third electrical node, and the firstelectrical node includes a first virtual output queue (VOQ). The methodincludes: sending, by the first electrical node, request information tothe second electrical node, where the request information is used torequest an expected data volume quota of the first VOQ, and the firstVOQ stores at least one first data packet to be sent to the secondelectrical node; receiving response information, where the responseinformation includes a target data volume quota; and sending the atleast one first data packet to the second electrical node via the atleast one optical node based on the target data volume quota. In theforegoing technical solution, the first electrical node sends therequest information to the second electrical node, receives the responseinformation from the second electrical node, and sends the at least onefirst data packet to the second electrical node via the at least oneoptical node based on the target data volume quota included in theresponse information. In this way, the first electrical node does notneed to distinguish between heavy traffic and light traffic. Thisreduces a data communication latency. In addition, data is sent based onthe target data volume quota. Therefore, an end-to-end QoS requirementis satisfied.

In a possible implementation of the first aspect, when there is a presetdata quota for the first VOQ, before the sending, by the firstelectrical node, request information to the second electrical node, themethod further includes: sending the at least one first data packet tothe second electrical node via the third electrical node based on thepreset data volume quota. In the foregoing possible implementation, whenthere is the preset data volume quota for the first electrical node, thefirst electrical node may directly send data based on the preset datavolume quota and does not need to wait a round-trip time. Therefore,data communication efficiency is improved.

In a possible implementation of the first aspect, the requestinformation includes a request sequence number SN, and a differencebetween the request SN and an initial SN is used to indicate theexpected data volume quota; or the request information includes a firstvalue, and the first value is used to indicate the expected data volumequota; and/or the response information includes a response sequencenumber SN, and a difference between the response SN and the initial SNis used to indicate the target data volume quota; or the responseinformation includes a second value, and the second value is used toindicate the target data volume quota. In the foregoing possibleimplementation, diversity is improved by carrying the expected datavolume quota in the request information and/or carrying the target datavolume quota in the response information.

In a possible implementation of the first aspect, the responseinformation further includes any one of the following: an identifier ofthe first electrical node, an identifier of the second electrical node,an identifier of the first VOQ, an identifier of the at least oneoptical node, an identifier of a sending path corresponding to the atleast one optical node, a volume quota of data to be sent on the atleast one optical node, or a sending slot corresponding to the at leastone optical node. In the foregoing possible implementation, the firstelectrical node may send data to the at least one optical node based ona corresponding volume quota of data to be sent and a correspondingsending slot. This reduces a latency in a data communication process,and increases a data communication rate.

In a possible implementation of the first aspect, the sending requestinformation to the second electrical node includes: sending the requestinformation to the second electrical node via the third electrical node;or sending a second data packet to the second electrical node via anyone of the at least one optical node, where the second data packetcarries the request information. In the foregoing possibleimplementation, flexibility of sending the request information by thefirst electrical node is improved. In addition, signaling interactionbetween nodes can be reduced when the request information is carried inthe second data packet.

3 In a possible implementation of the first aspect, the receivingresponse information includes: receiving response information sent bythe second electrical node via the third electrical node; or receiving athird data packet sent by the second electrical node via any one of theat least one optical node, where the third data packet carries theresponse information. In the foregoing possible implementation,flexibility of sending the response information by the second electricalnode is improved. In addition, signaling interaction between nodes canbe reduced when the request information is carried in the third datapacket.

According to a second aspect, a data communication method is providedand is applied to a data communication network including at least twoswitching layers, where the at least two switching layers include afirst layer and a second layer, the first layer includes a firstelectrical node and a second electrical node, the second layer includesat least one optical node and a third electrical node, and the firstelectrical node includes a first virtual output queue (VOQ). The methodincludes: receiving, by the third electrical node, request informationsent by the first electrical node, where the request information is usedto request an expected data volume quota of the first VOQ, and the firstVOQ stores at least one first data packet to be sent to the secondelectrical node; sending the request information to the secondelectrical node; receiving response information sent by the secondelectrical node, where the response information includes a target datavolume quota; and sending the response information to the firstelectrical node. In the foregoing technical solution, the thirdelectrical node sends the request information to the second electricalnode, and forwards the response information to the first electricalnode, so that the first electrical node sends the at least one firstdata packet to the second electrical node via the at least one opticalnode based on the target data volume quota included in the responseinformation. In this way, the first electrical node does not need todistinguish between heavy traffic and light traffic. This reduces a datacommunication latency. In addition, data is sent based on the targetdata volume quota. Therefore, an end-to-end QoS requirement issatisfied.

In a possible implementation of the second aspect, when there is apreset data quota for the first VOQ, before the receiving, by the thirdelectrical node, request information sent by the first electrical node,the method further includes: receiving the at least one first datapacket sent by the first electrical node based on the preset data volumequota; and sending the at least one first data packet to the secondelectrical node. In the foregoing possible implementation, when there isthe preset data volume quota for the first electrical node, the firstelectrical node may directly forward data via the third electrical nodebased on the preset data volume quota and does not need to wait around-trip time. Therefore, data communication efficiency is improved.

In a possible implementation of the second aspect, the requestinformation includes a request sequence number SN, and a differencebetween the request SN and an initial SN is used to indicate theexpected data volume quota; or the request information includes a firstvalue, and the first value is used to indicate the expected data volumequota; and/or the response information includes a response sequencenumber SN, and a difference between the response SN and the initial SNis used to indicate the target data volume quota; or the responseinformation includes a second value, and the second value is used toindicate the target data volume quota. In the foregoing possibleimplementation, diversity is improved by carrying the expected datavolume quota in the request information and/or carrying the target datavolume quota in the response information.

In a possible implementation of the second aspect, before the sendingthe response information to the first electrical node, the methodfurther includes: determining, based on the target data volume quota, avolume quota of data to be sent on each of the at least one opticalnode; where correspondingly, the response information further includesany one of the following: an identifier of the first electrical node, anidentifier of the second electrical node, an identifier of the firstVOQ, an identifier of the at least one optical node, an identifier of asending path corresponding to the at least one optical node, a volumequota of data to be sent on the at least one optical node, or a sendingslot corresponding to the at least one optical node. In the foregoingpossible implementation, the first electrical node may send data to theat least one optical node based on a corresponding volume quota of datato be sent and a corresponding sending slot. This reduces a latency in adata communication process, and increases a data communication rate.

In a possible implementation of the second aspect, the method furtherincludes: sending scheduling information to each of the at least oneoptical node, where the scheduling information includes at least one ofthe following information: the identifier of the first electrical node,the identifier of the second electrical node, the identifier of thefirst VOQ, an identifier of a sending path corresponding to the opticalnode, a volume quota of data to be sent on the optical node, or asending slot corresponding to the optical node. In the foregoingpossible implementation, each optical node may receive, based on acorresponding volume quota of data to be sent and a correspondingsending slot, data sent by the first electrical node. This reduces alatency in a data communication process, and increases a datacommunication rate.

According to a third aspect, a data communication method is provided andis applied to a data communication network including at least twoswitching layers, where the at least two switching layers include afirst layer and a second layer, the first layer includes a firstelectrical node and a second electrical node, the second layer includesat least one optical node and a third electrical node, and the firstelectrical node includes a first virtual output queue (VOQ). The methodincludes: receiving, by the second electrical node, request information,where the request information is used to request an expected data volumequota of the first VOQ, and the first VOQ stores at least one first datapacket to be sent to the second electrical node; sending responseinformation, where the response information includes a target datavolume quota; and receiving the at least one first data packet that issent by the first electrical node via the at least one optical nodebased on the target data volume quota. In the foregoing technicalsolution, the second electrical node receives the request informationsent by the first electrical node, and sends the response information,so that the first electrical node sends the at least one first datapacket to the second electrical node via the at least one optical nodebased on the target data volume quota included in the responseinformation. In this way, the first electrical node does not need todistinguish between heavy traffic and light traffic. This reduces a datacommunication latency. In addition, data is sent based on the targetdata volume quota. Therefore, an end-to-end QoS requirement issatisfied.

In a possible implementation of the third aspect, when there is a presetdata quota for the first VOQ, before the receiving request information,the method further includes: receiving the at least one first datapacket that is sent by the first electrical node to the secondelectrical node via the third electrical node based on the preset datavolume quota. In the foregoing possible implementation, when there isthe preset data volume quota for the first electrical node, the firstelectrical node may directly send data based on the preset data volumequota and does not need to wait a round-trip time. Therefore, datacommunication efficiency is improved.

In a possible implementation of the third aspect, the requestinformation includes a request sequence number SN, and a differencebetween the request SN and an initial SN is used to indicate theexpected data volume quota; or the request information includes a firstvalue, and the first value is used to indicate the expected data volumequota; and/or the response information includes a response sequencenumber SN, and a difference between the response SN and the initial SNis used to indicate the target data volume quota; or the responseinformation includes a second value, and the second value is used toindicate the target data volume quota. In the foregoing possibleimplementation, diversity is improved by carrying the expected datavolume quota in the request information and/or carrying the target datavolume quota in the response information.

In a possible implementation of the third aspect, the receiving, by thefirst electrical node, request information includes: receiving therequest information sent by the first electrical node via the thirdelectrical node; or receiving, via any one of the at least one opticalnode, a second data packet sent by the first electrical node, where thesecond data packet carries the request information. In the foregoingpossible implementation, flexibility of sending the request informationby the first electrical node is improved. In addition, signalinginteraction between nodes can be reduced when the request information iscarried in the second data packet.

In a possible implementation of the third aspect, the sending responseinformation includes: sending the response information to the firstelectrical node via the third electrical node; or sending a third datapacket to the first electrical node via any one of the at least oneoptical node, where the third data packet carries the responseinformation. In the foregoing possible implementation, flexibility ofsending the response information by the second electrical node isimproved. In addition, signaling interaction between nodes can bereduced when the request information is carried in the third datapacket.

According to a fourth aspect, a data communication apparatus isprovided. The data communication apparatus may implement a function ofthe data communication method provided in any one of the first aspect orthe possible implementations of the first aspect. The function may beimplemented by hardware, or may be implemented by hardware executingcorresponding software. The hardware or the software includes one ormore units corresponding to the function.

In a possible implementation of the fourth aspect, the datacommunication apparatus serves as a first electrical node and is appliedto a data communication network including at least two switching layers,the at least two switching layers include a first layer and a secondlayer, the first layer includes a first electrical node and a secondelectrical node, the second layer includes at least one optical node anda third electrical node, and the first electrical node includes a firstvirtual output queue (VOQ). A structure of the data communicationapparatus includes a processor, a memory, a communications interface,and a bus. The processor, the memory, and the communications interfaceare connected by the bus. The memory is configured to store programcode. The communications interface is configured to supportcommunication of the data communication apparatus. When the program codeis executed by the processor, the data communication apparatus isenabled to perform the following steps: sending request information tothe second electrical node, where the request information is used torequest an expected data volume quota of the first VOQ, and the firstVOQ stores at least one first data packet to be sent to the secondelectrical node; receiving response information, where the responseinformation includes a target data volume quota; and sending the atleast one first data packet to the second electrical node via the atleast one optical node based on the target data volume quota.

In a possible implementation of the fourth aspect, when there is apreset data quota for the first VOQ, the data communication apparatusfurther performs the following step: sending the at least one first datapacket to the second electrical node via the third electrical node basedon the preset data volume quota.

In a possible implementation of the fourth aspect, the requestinformation includes a request sequence number SN, and a differencebetween the request SN and an initial SN is used to indicate theexpected data volume quota; or the request information includes a firstvalue, and the first value is used to indicate the expected data volumequota; and/or the response information includes a response sequencenumber SN, and a difference between the response SN and the initial SNis used to indicate the target data volume quota; or the responseinformation includes a second value, and the second value is used toindicate the target data volume quota.

In a possible implementation of the fourth aspect, the responseinformation further includes any one of the following: an identifier ofthe first electrical node, an identifier of the second electrical node,an identifier of the first VOQ, an identifier of the at least oneoptical node, an identifier of a sending path corresponding to the atleast one optical node, a volume quota of data to be sent on the atleast one optical node, or a sending slot corresponding to the at leastone optical node.

In a possible implementation of the fourth aspect, the datacommunication apparatus further performs the following step: sending therequest information to the second electrical node via the thirdelectrical node; or sending a second data packet to the secondelectrical node via any one of the at least one optical node, where thesecond data packet carries the request information.

In a possible implementation of the fourth aspect, the datacommunication apparatus further performs the following step: receivingresponse information sent by the second electrical node via the thirdelectrical node; or receiving a third data packet sent by the secondelectrical node via any one of the at least one optical node, where thethird data packet carries the response information.

According to a fifth aspect, a data communication apparatus is provided.The data communication apparatus may implement a function of the datacommunication method provided in any one of the second aspect or thepossible implementations of the second aspect. The function may beimplemented by hardware, or may be implemented by hardware executingcorresponding software. The hardware or the software includes one ormore units corresponding to the function.

In a possible implementation of the fifth aspect, the data communicationapparatus serves as a third electrical node and is applied to a datacommunication network including at least two switching layers, the atleast two switching layers include a first layer and a second layer, thefirst layer includes a first electrical node and a second electricalnode, and the second layer includes at least one optical node and athird electrical node, and the first electrical node includes a firstvirtual output queue (VOQ). A structure of the data communicationapparatus includes a processor, a memory, a communications interface,and a bus. The processor, the memory, and the communications interfaceare connected by the bus. The memory is configured to store programcode. The communications interface is configured to supportcommunication of the data communication apparatus. When the program codeis executed by the processor, the data communication apparatus isenabled to perform the following step: receiving request informationsent by the first electrical node, where the request information is usedto request an expected data volume quota of the first VOQ, and the firstVOQ stores at least one first data packet to be sent to the secondelectrical node; sending the request information to the secondelectrical node; receiving response information sent by the secondelectrical node, where the response information includes a target datavolume quota; and sending the response information to the firstelectrical node.

In a possible implementation of the fifth aspect, the data communicationapparatus further performs the following step: when there is a presetdata quota for the first VOQ, receiving the at least one first datapacket sent by the first electrical node based on the preset data volumequota; and sending the at least one first data packet to the secondelectrical node.

In a possible implementation of the fifth aspect, the requestinformation includes a request sequence number SN, and a differencebetween the request SN and an initial SN is used to indicate theexpected data volume quota; or the request information includes a firstvalue, and the first value is used to indicate the expected data volumequota; and/or the response information includes a response sequencenumber SN, and a difference between the response SN and the initial SNis used to indicate the target data volume quota; or the responseinformation includes a second value, and the second value is used toindicate the target data volume quota.

In a possible implementation of the fifth aspect, the data communicationapparatus further performs the following step: determining, based on thetarget data volume quota, a volume quota of data to be sent on each ofthe at least one optical node; where correspondingly, the responseinformation further includes any one of the following: an identifier ofthe first electrical node, an identifier of the second electrical node,an identifier of the first VOQ, an identifier of the at least oneoptical node, an identifier of a sending path corresponding to the atleast one optical node, a volume quota of data to be sent on the atleast one optical node, or a sending slot corresponding to the at leastone optical node.

In a possible implementation of the fifth aspect, the data communicationapparatus further performs the following step: sending schedulinginformation to each of the at least one optical node, where thescheduling information includes at least one of the followinginformation: the identifier of the first electrical node, the identifierof the second electrical node, the identifier of the first VOQ, anidentifier of a sending path corresponding to the optical node, a volumequota of data to be sent on the optical node, or a sending slotcorresponding to the optical node.

According to a sixth aspect, a data communication apparatus is provided.The data communication apparatus may implement a function of the datacommunication method provided in any one of the third aspect or thepossible implementations of the third aspect. The function may beimplemented by hardware, or may be implemented by hardware executingcorresponding software. The hardware or the software includes one ormore units corresponding to the function.

In a possible implementation of the sixth aspect, the data communicationapparatus serves as a second electrical node and is applied to a datacommunication network including at least two switching layers, the atleast two switching layers include a first layer and a second layer, thefirst layer includes a first electrical node and a second electricalnode, and the second layer includes at least one optical node and athird electrical node, and the first electrical node includes a firstvirtual output queue (VOQ). A structure of the data communicationapparatus includes a processor, a memory, a communications interface,and a bus. The processor, the memory, and the communications interfaceare connected by the bus. The memory is configured to store programcode. The communications interface is configured to supportcommunication of the data communication apparatus. When the program codeis executed by the processor, the data communication apparatus isenabled to perform the following step: receiving request information,where the request information is used to request an expected data volumequota of the first VOQ, and the first VOQ stores at least one first datapacket to be sent to the second electrical node; sending responseinformation, where the response information includes a target datavolume quota; and receiving the at least one first data packet that issent by the first electrical node via the at least one optical nodebased on the target data volume quota.

In a possible implementation of the sixth aspect, the data communicationapparatus further performs the following step: when there is a presetdata quota for the first VOQ, receiving the at least one first datapacket that is sent by the first electrical node to the secondelectrical node via the third electrical node based on the preset datavolume quota.

In a possible implementation of the sixth aspect, the requestinformation includes a request sequence number SN, and a differencebetween the request SN and an initial SN is used to indicate theexpected data volume quota; or the request information includes a firstvalue, and the first value is used to indicate the expected data volumequota; and/or the response information includes a response sequencenumber SN, and a difference between the response SN and the initial SNis used to indicate the target data volume quota; or the responseinformation includes a second value, and the second value is used toindicate the target data volume quota.

In a possible implementation of the sixth aspect, the data communicationapparatus further performs the following step: receiving the requestinformation sent by the first electrical node via the third electricalnode; or receiving, via any one of the at least one optical node, asecond data packet sent by the first electrical node, where the seconddata packet carries the request information.

In a possible implementation of the sixth aspect, the data communicationapparatus further performs the following step: sending the responseinformation to the first electrical node via the third electrical node;or sending a third data packet to the first electrical node via any oneof the at least one optical node, where the third data packet carriesthe response information.

According to a seventh aspect, a computer-readable storage medium isprovided. The computer-readable storage medium stores a computer programor an instruction, and when the computer program or the instruction isrun, the data communication method provided in any one of the firstaspect or the possible implementations of the first aspect is performed.

According to an eighth aspect, a computer-readable storage medium isprovided. The computer-readable storage medium stores a computer programor an instruction, and when the computer program or the instruction isrun, the data communication method provided in any one of the secondaspect or the possible implementations of the second aspect isperformed.

According to a ninth aspect, a computer-readable storage medium isprovided. The computer-readable storage medium stores a computer programor an instruction, and when the computer program or the instruction isrun, the data communication method provided in any one of the thirdaspect or the possible implementations of the third aspect is performed.

According to a tenth aspect, a computer program product is provided. Thecomputer program product includes a computer program or an instruction,and when the computer program or the instruction is run, the datacommunication method provided in any one of the first aspect or thepossible implementations of the first aspect is performed.

According to an eleventh aspect, a computer program product is provided.The computer program product includes a computer program or aninstruction, and when the computer program or the instruction is run,the data communication method provided in any one of the second aspector the possible implementations of the second aspect is performed.

According to a twelfth aspect, a computer program product is provided.The computer program product includes a computer program or aninstruction, and when the computer program or the instruction is run,the data communication method provided in any one of the third aspect orthe possible implementations of the third aspect is performed.

According to a thirteenth aspect, a data communication network isprovided. The data communication network includes at least two switchinglayers, where the at least two switching layers include a first layerand a second layer, the first layer includes a first electrical node anda second electrical node, the second layer includes at least one opticalnode and a third electrical node, and the first electrical node includesa first virtual output queue (VOQ). The first electrical node may be thefirst electrical node provided in the foregoing aspects, and isconfigured to support the first electrical node in performing the datacommunication method provided in any one of the first aspect or thepossible implementations of the first aspect; and/or the thirdelectrical node is the third electrical node provided in the foregoingaspects, and is configured to support the third electrical node inperforming the data communication method provided in any one of thesecond aspect or the possible implementations of the second aspect;and/or the second electrical node is the second electrical node providedin the foregoing aspects, and is configured to support the secondelectrical node in performing the data communication method provided inany one of the third aspect or the possible implementations of the thirdaspect.

It may be understood that any one of the apparatus for the datacommunication method, the computer storage medium, the computer programproduct, or the data communication network provided above is configuredto perform the corresponding method provided above. Therefore, forbeneficial effects that can be achieved by the apparatus, the computerstorage medium, the computer program product, or the data communicationnetwork, refer to the beneficial effects in the corresponding methodprovided above. Details are not described herein again.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic structural diagram of a data communicationnetwork:

FIG. 2 is a first schematic structural diagram of a data communicationnetwork according to an embodiment of this application;

FIG. 3 is a second schematic structural diagram of a data communicationnetwork according to an embodiment of this application;

FIG. 4 is a schematic structural diagram of a source node according toan embodiment of this application:

FIG. 5 is a schematic structural diagram of a destination node accordingto an embodiment of this application;

FIG. 6 is a first schematic flowchart of a data communication methodaccording to an embodiment of this application;

FIG. 7 is a second schematic flowchart of a data communication methodaccording to an embodiment of this application;

FIG. 8 is a third schematic flowchart of a data communication methodaccording to an embodiment of this application;

FIG. 9 is a third schematic structural diagram of a data communicationnetwork according to an embodiment of this application:

FIG. 10 is a first schematic structural diagram of a data communicationapparatus according to an embodiment of this application;

FIG. 11 is a second schematic structural diagram of a data communicationapparatus according to an embodiment of this application:

FIG. 12 is a third schematic structural diagram of a data communicationapparatus according to an embodiment of this application:

FIG. 13 is a fourth schematic structural diagram of a data communicationapparatus according to an embodiment of this application;

FIG. 14 is a fifth schematic structural diagram of a data communicationapparatus according to an embodiment of this application; and

FIG. 15 is a sixth schematic structural diagram of a data communicationapparatus according to an embodiment of this application.

DESCRIPTION OF EMBODIMENTS

The following describes the technical solutions in the embodiments ofthis application with reference to the accompanying drawings in theembodiments of this application. In the descriptions of thisapplication, unless otherwise specified, “a plurality of” means two ormore. In addition, to clearly describe the technical solutions in theembodiments of this application, terms such as “first” and “second” areused in the embodiments of this application to distinguish between sameitems or similar items that have basically same functions and purposes.A person skilled in the art may understand that the terms such as“first” and “second” do not limit a quantity and an execution sequence.

The embodiments of this application are applied to a data communicationnetwork in which a hybrid networking mode is used. In a typicalarchitecture of the data communication network, a networking modeincluding three switching layers (namely, an access layer, anaggregation layer, and a core layer), or a networking mode including twoswitching layers (namely, an access layer and a core layer) may be used.A plurality of nodes may be included at each switching layer in the datacommunication network. For example, the access layer may include aplurality of access (Access) nodes, the aggregation layer includes aplurality of aggregation (Aggregation) nodes, and the core layerincludes a plurality of core (Core) nodes. The access nodes and theaggregation nodes are all electrical switching nodes (which may also bereferred to as E nodes). The core nodes include both an electricalswitching node and an optical switching node (which may also be referredto as O nodes).

When a hybrid networking mode including three switching layers is usedfor the architecture of the data communication network, a downstreamport of the access node is connected to a server on which data trafficneeds to be exchanged, an upstream port of the access node is connectedto a downstream port of the aggregation node, and an upstream port ofthe aggregation node is connected to the core node. The aggregationlayer and the access layer may be divided into a plurality of groups(Pod). One pod may include a plurality of access nodes and a pluralityof aggregation nodes, and each of the access nodes is connected to allof the plurality of aggregation nodes. In addition, the plurality ofcore nodes at the core layer may be divided into a plurality of coreplanes, and each of the core planes is connected to differentaggregation nodes in different pods. Alternatively, the plurality ofcore nodes at the core layer are not divided into core planes,electrical switching nodes at the core layer are connected to allaggregation nodes, and optical switching nodes each are connected tosome or all of the aggregation nodes.

When a hybrid networking mode including two switching layers is used forthe architecture of the data communication network, a downstream port ofthe access node is connected to a server on which data traffic needs tobe exchanged, and an upstream port of the access node is directlyconnected to the core node. The access layer may be divided into aplurality of groups (Pod). One pod may include a plurality of accessnodes. In addition, the plurality of core nodes at the core layer may bedivided into a plurality of core planes, and each of the core planes isconnected to different access nodes in different pods. Alternatively,the plurality of core nodes at the core layer are not divided into coreplanes, electrical switching nodes at the core layer are connected toall access nodes, and optical switching nodes each are connected to someor all of the access nodes.

In the embodiments of this application, an example in which a hybridnetworking mode including three switching layers is used for anarchitecture of a data communication network and a core layer is dividedinto a plurality of core planes is used for description. FIG. 2 is aschematic architectural diagram of a data communication network.Referring to FIG. 2, the data communication network includes an accesslayer, an aggregation layer, and a core layer.

As shown in FIG. 2, only an example in which the data communicationnetwork includes three pods, one pod includes three access nodes andfour aggregation nodes, and each core plane includes two core nodes isused for description. Access nodes in FIG. 2 may be denoted as A1 to A9,aggregation nodes may be denoted as B1 to B12, and core nodes may bedenoted as C1 to C8 (C1, C3, C5, and C7 are electrical switching nodes,and C2, C4, C6, and C8 are optical switching nodes). The three pods area Pod 1 to a Pod 3.

When data traffic is to be exchanged between servers connected todifferent access nodes in one pod, the data traffic may be exchangedthrough an aggregation node that is in a same pod as the access nodes.For example, data traffic needs to be exchanged between serversconnected to the access node A1 and the access node A3. In this case,the access node A1 may send, through the aggregation node B1, a datastream of a server connected to the access node A1 to the access nodeA3. When data traffic is to be exchanged between servers connected toaccess nodes in different pods, the data traffic may be exchangedthrough an aggregation node that is in a same pod as the access node anda core node that is connected to the aggregation node. For example, datatraffic needs to be exchanged between servers connected to the accessnode A1 and the access node A5. In this case, the access node A1 maysend a data stream of a server connected to the access node A1 to theaggregation node B1. Then, the data stream of the server connected tothe access node A1 is forwarded by the aggregation node B1 to the corenode C1 and is sent by the core node C1 to the access node A5 throughthe aggregation node B5.

It should be noted that a structure, shown in FIG. 2, of the datacommunication network is merely an example, and does not constitute alimitation on the structure of the data communication network. In actualapplication, each switching layer of the data communication network mayalternatively include more or fewer nodes than those shown in thefigure, or the data communication network may alternatively be a networkincluding two switching layers, or a plurality of core nodes at the corelayer may be or may not be divided into a plurality of core planes. Thisis not specifically limited in this embodiment of this application.

For ease of understanding, as shown in FIG. 3, a plurality ofaggregation nodes (for example, n aggregation nodes) connected to a samecore plane and a plurality of core nodes in one core plane in a datacommunication network including three switching layers may be consideredas an n×n switch fabric (Switch Fabric, SF) system. The n×n SF includesn source nodes (Source, S), n destination nodes (Destination, D), and mintermediate core nodes (Switch Element, SE). Si and Di in FIG. 3 are asame aggregation node (i sequentially takes a value from 1 to n). To bespecific, the n source nodes and the n destination nodes are naggregation nodes that are connected to a same core plane and that areclassified based on functions when the n aggregation nodes each are usedas a sending node and a receiving node. Each of the n aggregation nodesmay include a plurality of ports. For S, the plurality of ports areinput ports (Input Port); and for D, the plurality of ports are outputports (Output Port). The data communication network including threeswitching layers may be considered as a network including a plurality ofswitch fabrics. All switch fabrics use a same control mechanism.

Similarly, the data communication network including two switching layersmay also be considered as a network including a plurality of switchfabrics. A difference lies in that the n source nodes and the ndestination nodes are n access nodes that are connected to a same coreplane and that are classified based on functions when the n access nodeseach are used as a sending node and a receiving node. Details are notdescribed in this embodiment of this application.

In the switch fabric shown in FIG. 3, a data packet (Packet) receivedfrom S may be forwarded to D. When the data packet passes through theSE, an original format of a variable-length packet (Variable-lengthPacket) may be maintained. Alternatively, S may first fragment the datapacket into cells (Cell) for sending, and then, after receiving all thecells, D assembles all the cells into the complete data packet. In sucha switch fabric, S can usually evenly distribute received data packetsto all SEs. The data packet sent by S generally carries informationabout D, and the SE forwards the data packet to corresponding D based onthe carried information.

S receives a data packet from outside the system through the input port.Generally, there are a plurality of virtual output queues (VirtualOutput Queue, VOQ) in S that are used to buffer data packets destinedfor different Ds (or to buffer data packets destined for differentoutput ports of different Ds; or a plurality of VOQs correspond to flowsof a finer granularity, to be specific, a plurality of VOQs are used tobuffer data packets of flows of different granularities). The VOQ may beused to ensure end-to-end QoS, and is a means for preventinghead-of-line blocking (Head-of-line Blocking, HOL Blocking). For the n×nswitch fabric, each S generally has at least n VOQs corresponding to nDs. If division is further performed based on the output port of D or arequirement of a higher granularity, more VOQs may alternatively beincluded.

FIG. 4 is a schematic structural diagram of a source node (S). Sincludes a plurality of input ports, a queue manager (QM), an ingressscheduler (Ingress Scheduler, ISC), and a fabric interface. The QM maybe configured to manage K VOQs (K is a positive integer), and the ISCmay be configured to schedule the K VOQs in the QM. A data packet outputthrough scheduling may be fragmented into cells through the fabricinterface, and the cell is added with a cell header (Header) and is sentto an SE. Alternatively, a data packet is directly sent to an SE.

FIG. 5 is a schematic structural diagram of a destination node (D). TheD includes a plurality of output ports, a queue manager (Queue Manager,QM), an egress scheduler (Egress Scheduler, ESC), and a fabric interface(Fabric Interface). The QM may be configured to manage L output queues(Output Queue, OQ), where L is a positive integer. The L OQs are used tobuffer data packets destined for different outputs, and the ESC may beconfigured to schedule the L OQs in the QM.

For example, an ISC in S may send a request to corresponding D based ona status of a VOQ in S. After receiving the request, the ESC in Dcompletes scheduling, and notifies the ISC of a scheduling result. Basedon the scheduling result, the ISC schedules a data packet in the VOQ inS to be dequeued. In a scheduling process of the ESC in D, QoS featuresof different requests and congestion of each OQ in D may be considered.

A person skilled in the art may understand that structures of the datacommunication network, the source node, and the destination node thatare described in the embodiments of this application are intended todescribe the technical solutions in the embodiments of this applicationmore clearly, and do not constitute a limitation on the technicalsolutions provided in the embodiments of this application.

FIG. 6 is a schematic structural diagram of a data communication methodaccording to an embodiment of this application. The data communicationmethod is applied to a data communication network including at least twoswitching layers, where the at least two switching layers include afirst layer and a second layer, the first layer includes a firstelectrical node and a second electrical node, the second layer includesat least one optical node and a third electrical node, the firstelectrical node includes a first virtual output queue (VOQ). The methodincludes the following steps.

Step 601: The first electrical node sends request information to thesecond electrical node, where the request information is used to requestan expected data volume quota of the first VOQ, and the first VOQ storesat least one first data packet to be sent to the second electrical node.

When the data communication network includes two switching layers, thefirst layer may be an access layer, and the first electrical node andthe second electrical node may be access nodes; and the second layer maybe a core layer, and the at least one optical node and the thirdelectrical node may be core nodes. When the data communication networkincludes three switching layers, the first layer may be an aggregationlayer, and the first electrical node and the second electrical node maybe aggregation nodes; and the second layer may be a core layer, and theat least one optical node and the third electrical node may be corenodes.

In addition, the first electrical node may be a source node, and thesecond electrical node may be a destination node. The first electricalnode may include a plurality of VOQs, and each of the VOQs maycorrespond to a different destination node. The first VOQ is any one ofthe plurality of VOQs, and is used to buffer a data packet to be sent tothe second electrical node. In other words, a destination nodecorresponding to the first VOQ is the second electrical node.

In addition, the at least one first data packet is a data packet that isreceived by the first electrical node from outside a system through aninput port and that is to be sent to the second electrical node. The atleast one first data packet may include one or more first data packets.Each first data packet may include different data and may correspond toa same data volume or a different data volume.

Specifically, when receiving, through the input port, the at least onefirst data packet to be sent to the second electrical node, the firstelectrical node may store the at least one first data packet in thefirst VOQ corresponding to the second electrical node. When the firstelectrical node is to send the at least one first data packet to thesecond electrical node through the data communication network, the firstelectrical node may send, to the second electrical node, the requestinformation used to request the expected data volume quota of the firstVOQ. The request information may be generated by the first electricalnode. The expected data volume quota may indicate a data volume of datathat is stored in the first VOQ and that the first electrical nodeexpects to send to the second electrical node. For example, the firstVOQ stores 10 first data packets, and the first electrical node expectsto send the first five first data packets to the second electrical node.In this case, the expected data volume quota may be a total data volumeof the first five first data packets.

Optionally, the first electrical node may send the request informationto the third electrical node. When receiving the request information,the third electrical node may forward the request information to thesecond electrical node. Alternatively, when the first electrical nodehas transmitted data to the second electrical node via the at least oneoptical node, the first electrical node may include the requestinformation in the transmitted data, for example, the first electricalnode may include the request information in a second data packet, andsend the second data packet including the request information to any oneof the at least one optical node. Then, the optical node forwards thesecond data packet including the request information to the secondelectrical node.

In addition, the request information may include information used todirectly indicate the expected data volume quota, or may includeinformation used to indirectly indicate the expected data volume quota.When the request information includes the information used to directlyindicate the expected data volume quota, the information may be a valuecorresponding to the expected data volume quota. For example, therequest information includes a value 200, and the value 200 is used toindicate that the expected data volume quota is 200 KB. When the requestinformation includes the information used to indirectly indicate theexpected data volume quota, the following two manners may be used forindication. Specifically, the request information includes a requestsequence number (Sequence Number, SN), and a difference between therequest SN and an initial SN is used to indicate the expected datavolume quota. The initial SN may be a current SN corresponding to thefirst VOQ, and may be stored by the first electrical node and the secondelectrical node. For example, if the request SN is 10 and the initial SNis 4, the expected data volume quota may be (10−4)×ΔF. Alternatively,the request information includes a first value, and the first value isused to indicate the expected data volume quota. For example, if thefirst value is 6, the expected data volume quota may be 6×ΔF.

It should be noted that ΔF may be a unit data volume. For example, ΔF is4 KB or 8 KB. The unit data volume may be preset or preconfigured.

Step 602: The second electrical node receives the request information.The request information in step 602 is the same as that in step 601. Fordetails, refer to related descriptions. Details are not described hereinin this embodiment of this application again.

When receiving the request information, the second electrical node mayparse the request information, to obtain the expected data volume quotaincluded in the request information.

Step 603: The second electrical node sends response information, wherethe response information includes a target data volume quota.

After receiving the request information, the second electrical node maydetermine the target data volume quota based on the request information,or determine the target data volume quota based on the requestinformation, a status of a VOQ of the second electrical node, and thelike. The target data volume quota is a volume that is of data allowedto be sent by the first electrical node and that is determined by thesecond electrical node. The target data volume quota may be equal to orless than the expected data volume quota. Certainly, the target datavolume quota may be greater than the expected data volume quota. Forexample, when the VOQ of the second electrical node is in an idle state,and a volume of data that can be received by the second electrical nodeis greater than or equal to the expected data volume quota, the secondelectrical node may determine the expected data volume quota as thetarget data volume quota, or determine a target data volume quota thatis greater than the expected data volume quota. When the VOQ of thesecond electrical node is in a relatively congested state, and a volumeof data that can be received by the second electrical node is less thanthe expected data volume quota, the second electrical node may determinea target data volume quota that is less than the expected data volumequota. Then, the second electrical node may send the responseinformation, and include the target data volume quota in the responseinformation. The response information may be generated by the secondelectrical node.

Optionally, the second electrical node may send the response informationto the third electrical node. When receiving the response information,the third electrical node may forward the response information to thefirst electrical node. Alternatively, when the second electrical nodehas transmitted data to the first electrical node via the at least oneoptical node, the second electrical node may include the responseinformation in the transmitted data, for example, the first electricalnode may include the response information in a third data packet, andsend the third data packet including the response information to any oneof the at least one optical node, so that the optical node forwards thethird data packet including the response information to the firstelectrical node.

In addition, the response information may include information used todirectly indicate the target data volume quota, or may includeinformation used to indirectly indicate the target data volume quota. Itshould be noted that a manner of indicating the target data volume quotain the response information is similar to a manner of indicating theexpected data volume quota in the request information. For details,refer to related descriptions. Details are not described herein in thisembodiment of this application again.

Further, the response information may include at least one of thefollowing: an identifier of the first electrical node, an identifier ofthe second electrical node, an identifier of the first VOQ, anidentifier of the at least one optical node, or an identifier of asending path of the at least one first data packet.

The identifier of the first electrical node may be an address, a number,or the like of the first electrical node. The identifier of the secondelectrical node may be an address, a number, or the like of the secondelectrical node. The identifier of the first VOQ may be a number, or thelike of the first VOQ. The identifier of the at least one optical nodemay include an identifier of one optical node or identifiers of aplurality of optical nodes. An identifier of each optical node may be anaddress, a number, or the like of the optical node. The sending path ofthe at least one first data packet may include one or more paths, andeach path may have a corresponding path identifier. For example, thepath identifier is a routing table corresponding to a path. When the atleast one optical node includes one optical node, the sending path mayinclude one path. When the at least one optical node includes aplurality of optical nodes, the sending path may include a plurality ofpaths.

Step 604: After receiving the response information, the first electricalnode sends the at least one first data packet to the second electricalnode via the at least one optical node based on the target data volumequota.

When receiving the response information, the first electrical node mayparse the response information to obtain the target data volume quota,and send the first data packet to each of the at least one optical nodebased on the target data volume quota. When each of the at least oneoptical node receives the first data packet, the at least one opticalnode forwards the received first data packet to the second electricalnode.

For example, the target data volume quota is 100 KB, a total data volumeof the first four data packets in the at least one first data packet is100 KB, and the at least one optical node includes two optical nodes. Inthis case, the first electrical node may send the first two first datapackets to a first optical node in the two optical nodes, and send thelast two first data packets to a second optical node, so that the twooptical nodes forward the received first data packets to the secondelectrical node. Alternatively, the first electrical node may send thefirst three first data packets to a first optical node in the twooptical nodes, and send the last one first data packet to a secondoptical node, so that the two optical nodes forward the received firstdata packets to the second electrical node. Alternatively, the firstelectrical node may send the first one first data packet to a firstoptical node in the two optical nodes, and send the last three firstdata packets to a second optical node, so that the two optical nodesforward the received first data packets to the second electrical node.This is not specifically limited in this embodiment of this application.

Optionally, the first electrical node may determine the at least oneoptical node based on the response information. For example, the firstelectrical node determines the at least one optical node based on theidentifier of the at least one optical node included in the responseinformation. Alternatively, the first electrical node determines the atleast one optical node based on the identifier that is of the sendingpath of the at least one first data packet and that is included in theresponse information. Alternatively, before the first electrical nodesends the at least one first data packet, it may be configured that thefirst electrical node forwards the first data packet via the at leastone optical node, or the like. This is not specifically limited in thisembodiment of this application.

Step 605: The second electrical node receives the at least one firstdata packet.

The first electrical node sends the at least one first data packet tothe at least one optical node, and each of the at least one optical nodeforwards the received first data packet to the second electrical node.In this case, the second electrical node may receive the at least onefirst data packet.

Further, the target data volume quota is less than a total data volumeof the at least one first data packet. In other words, the firstelectrical node does not send all of the at least one first data packetto the second electrical node based on the target data volume quota. Inthis case, the first electrical node and the second electrical node mayfurther repeat steps 601 to 605, to send all of the at least one firstdata packet to the second electrical node.

In this embodiment of this application, when the first electrical nodeis to send the at least one first data packet to the second electricalnode, the first electrical node may send the request information to thesecond electrical node and receive the response information sent by thesecond electrical node. Then, the first electrical node sends the atleast one first data packet to the second electrical node via the atleast one optical node based on the target data volume quota included inthe response information. In this way, the first electrical node doesnot need to distinguish between heavy traffic and light traffic. Thisreduces a traffic buffer latency. In addition, the first electrical nodemay send data traffic via the optical node based on the target datavolume quota. Therefore, an end-to-end QoS requirement is satisfied.

Further, with reference to FIG. 6, referring to FIG. 7, the methodfurther includes steps 600 a and 600 b before step 601.

Step 600 a: The first electrical node sends the at least one first datapacket to the second electrical node via the third electrical node basedon a preset data volume quota.

When there is the preset data volume quota for the first electricalnode, the first electrical node may directly send the at least one firstdata packet to the third electrical node based on the preset data volumequota. When receiving the first data packet, the third electrical nodemay forward the received first data packet to the second electricalnode. First data packets sent by the first electrical node based on thepreset data volume quota may be some or all of the at least one firstdata packet. A quantity of sent first data packets is related to thepreset data volume quota.

The preset data volume quota may be preset. For example, the preset datavolume quota may be 50 KB, 100 KB, 150 KB, or the like. This is notspecifically limited in this embodiment of this application.

Further, the preset data volume quota is less than the total data volumeof the at least one first data packet. In other words, the firstelectrical node does not send all of the at least one first data packetto the second electrical node based on the preset data volume quota. Inthis case, the first electrical node and the second electrical node mayfurther perform steps 601 to 605, so that each of the at least one firstdata packet is sent to the second electrical node.

For example, the first electrical node may send the some or all of thedata packets to the second electrical node via the third electrical nodebased on the preset data volume quota and does not need to wait around-trip time (Round-Trip Time, RTT).

Step 600 b: The second electrical node receives the at least one firstdata packet sent by the first electrical node via the third electricalnode.

When the first electrical node sends the at least one first data packetto the third electrical node, the third electrical node may forward thereceived first data packet to the second electrical node, so that thesecond electrical node may receive the at least one first data packet.

In this embodiment of this application, when sending the at least onefirst data packet to the second electrical node, the first electricalnode may send the first data packet to the second electrical node viathe third electrical node based on the preset data volume quota. In thisway, signaling interaction between nodes may be reduced and datatransmission efficiency may be improved.

Further, with reference to FIG. 6, referring to FIG. 8, the methodfurther includes steps 603 a and 603 b before step 604 after step 603.

Step 603 a: The third electrical node determines, based on the targetdata volume quota, a volume quota of data to be sent on each of the atleast one optical node.

In a process in which the second electrical node sends the responseinformation to the first electrical node via the third electrical node,when receiving the response information sent by the second electricalnode, the third electrical node may obtain the target data volume quotaincluded in the response information, and determine, based on the targetdata volume quota, the volume quota of data to be sent on each of the atleast one optical node. In addition, the third electrical node mayfurther determine a sending slot (Slot) corresponding to the at leastone optical node.

Correspondingly, when the third electrical node sends the responseinformation to the first electrical node, the response information mayfurther include at least one of the following information: a volumequota of data to be sent on the at least one optical node or a sendingslot corresponding to the at least one optical node.

The at least one optical node includes one or more optical nodes, andthe volume quota of data to be sent on each optical node is a datavolume of the first data packet sent by the first electrical node toeach of the at least one optical node when the first electrical nodesends the at least one first data packet to the second electrical nodevia the optical node. Different optical nodes may have a same volumequota of data to be sent or different volume quotas of data to be sent.This is not specifically limited in this embodiment of this application.

In addition, the sending slot corresponding to the at least one opticalnode includes a sending slot corresponding to one optical node orsending slots corresponding to a plurality of optical nodes. The sendingslot corresponding to one optical node may be a sending slot in whichthe first electrical node sends the first data packet to the opticalnode. Therefore, the optical node may receive, in a corresponding slot,the first data packet sent by the first electrical node. Differentoptical nodes correspond to different sending slots.

For example, the at least one optical node includes three optical nodes(for example, optical nodes 1 to 3), the target data volume quota is 250KB, volume quotas of data to be sent on the optical nodes 1 to 3 may be100 KB, 100 KB, and 50 KB respectively, and sending slots correspondingto the optical nodes 1 to 3 may be slots 1, 2, and 3 respectively. It isassumed that data volumes of all first data packets are the same and are50 KB. In this case, when the first electrical node receives theresponse information and sends the first data packet to the at least oneoptical node, the first electrical node may send two first data packets(that is, a data volume of 100 KB) to the optical node 1 in the slot 1,send two first data packets (that is, a data volume of 100 KB) to theoptical node 2 in the slot 2, and send one first data packet (that is, adata volume of 50 KB) to the optical node 3 in the slot 3.

Specifically, when sending the response information to the firstelectrical node, the third electrical node may include, in the responseinformation, at least one of the volume quota of data to be sent on theat least one optical node or the sending slot corresponding to the atleast one optical node; and send the response information to the firstelectrical node. In this way, when sending the at least one first datapacket to the second electrical node via the at least one optical node,the first electrical node sends the at least one first data packet basedon the volume quota of data to be sent on each optical node in theresponse information and/or a sending slot corresponding to each opticalnode in the response information.

Optionally, the third electrical node may send at least one of thevolume quota of data to be sent on the at least one optical node or thesending slot corresponding to the at least one optical node to the firstelectrical node through other information different from the responseinformation. Signaling interaction between nodes may be reduced by usingthe response information to carry the at least one of the volume quotaof data to be sent on the at least one optical node or the sending slotcorresponding to the at least one optical node. This is not specificallylimited in this embodiment of this application.

Step 603 b: The third electrical node sends scheduling information toeach of the at least one optical node.

The scheduling information includes at least one of the followinginformation: the identifier of the first electrical node, the identifierof the second electrical node, the identifier of the first VOQ, anidentifier of a sending path corresponding to the optical node, thevolume quota of data to be sent on the optical node, or a sending slotcorresponding to the optical node.

When determining the volume quota of data to be sent on the at least oneoptical node and/or the sending slot corresponding to the at least oneoptical node, the third electrical node may generate the schedulinginformation, and send the scheduling information to each of the at leastone optical node. In this way, each optical node receives schedulinginformation corresponding to the optical node, receives, based on thescheduling information corresponding to the optical node, the first datapacket sent by the first electrical node, and sends the received firstdata packet to the second electrical node.

It should be noted that description about each piece of informationincluded in the scheduling information is consistent with thatcorresponding to the response information in the foregoing embodiment.For details, refer to the foregoing description. Details are notdescribed in this embodiment of this application again.

For ease of understanding, a data communication network shown in FIG. 9is used as an example herein to describe the method in this application.The data communication network shown in FIG. 9 includes an access layer,an aggregation layer, and a core layer. The access layer and theaggregation layer are divided into 48 pods (that is, pods 0 to 47). Eachpod includes two access nodes (that is, A1 to A2) and a plurality ofaggregation nodes (that is, S1 to Sn/D1 to Dn). Each plane at the corelayer includes 48 core nodes (C0 to C47). C0 is an electrical node, andC1 to C47 are optical nodes. It is assumed that a first electrical nodeis S1 in the pod 0, a second electrical node is D1 in the pod 47, athird electrical node is C0 on a first plane, and at least one opticalnode includes C1 to C47 on the first plane.

When the first electrical node (S) sends at least one first data packetto the second electrical node (D1), data communication paths between Sand D1 may be shown as P1 to P4 in FIG. 9. When the at least one firstdata packet is light traffic and there is a preset data volume quota forS1, S may send the at least one first data packet to D1 through the pathP1. Alternatively, S1 sends request information to D1 through the pathP1, and D1 sends response information to S through paths P2 and P3. Whenforwarding the response information, C0 in the first plane may allocatea volume quota of data to be sent and a sending slot for each of C1 toC47 on the first plane, and send, to S1, the response informationcarrying the volume quota of data to be sent and the sending slot. Whenreceiving the response information, S1 may sequentially send the atleast one first data packet to the second electrical node through thepath P4 based on the volume quota of data to be sent, the sending slot,and the like that correspond to each optical node. The path P4 is a pathon which S1 sends the first data packet to the second electrical nodevia the at least one optical node (for example, C1 to C47 on the firstplane). The path P4 may include a plurality of paths.

In the data communication method provided in this embodiment of thisapplication, data communication is performed based on an end-to-end (endto end, E2E) scheduling mechanism. Therefore, heavy traffic and lighttraffic do not need to be first distinguished in current hybridnetworking. This simplifies a design of a control plane for an opticalnode, reduces buffer pressure of aggregation nodes, and provides higherQoS.

The foregoing mainly describes the solutions provided in the embodimentsof this application from the perspective of interaction between nodes.It may be understood that, to implement the foregoing functions, thenetwork elements, such as the first electrical node, the secondelectrical node, and the third electrical node, include correspondinghardware structures and/or software modules for performing thefunctions. A person skilled in the art should easily be aware that, incombination with the examples described in the embodiments disclosed inthis specification, units and algorithm steps may be implemented byhardware or a combination of hardware and computer software in thisapplication. Whether a function is performed by hardware or hardwaredriven by computer software depends on particular applications anddesign constraints of the technical solutions. A person skilled in theart may use different methods to implement the described functions foreach particular application, but it should not be considered that theimplementation goes beyond the scope of this application.

In the embodiments of this application, function modules in the firstelectrical node, the second electrical node, and the third electricalnode may be obtained through division based on the foregoing methodexamples. For example, function modules may be obtained through divisionbased on corresponding functions, or two or more functions may beintegrated into one module. The integrated module may be implemented ina form of hardware, or may be implemented in a form of a softwarefunction module. It should be noted that module division in theembodiments of this application is an example, and is merely a logicalfunction division. In actual implementation, another division manner maybe used. Descriptions are provided below by using an example in whichfunction modules are obtained through division based on correspondingfunctions.

When an integrated unit is used. FIG. 10 is a possible schematicstructural diagram of a data communication apparatus used in theforegoing embodiment. The data communication apparatus may be a firstelectrical node or a chip built in the first electrical node, and thedata communication apparatus includes a sending unit 1001 and areceiving unit 1002. The sending unit 1001 is configured to support thedata communication apparatus in performing step 601, step 604, and/orstep 600 a in the method embodiment. The receiving unit 1002 supportsthe data communication apparatus in performing a step of receiving theresponse information sent in step 603 in the method embodiment.Optionally, the data communication apparatus may further include aprocessing unit 1003, and the processing unit 1003 is configured toperform a step of generating request information and/or a step ofparsing response information by the data communication apparatus. Allrelated content of the steps in the foregoing method embodiment may becited in function descriptions of corresponding function modules.Details are not described herein again.

Based on hardware implementation, the processing unit 1003 in thisapplication may be a processor of the data communication apparatus, thesending unit 1001 may be a transmitter of the data communicationapparatus, and the receiving unit 1002 may be a receiver of the datacommunication apparatus. The transmitter and the receiver may be usuallyintegrated together to serve as a transceiver. Specifically, thetransceiver may also be referred to as a communications interface.

FIG. 11 is a schematic diagram of a possible logical structure of a datacommunication apparatus used in the foregoing embodiment provided in theembodiments of this application. The data communication apparatus may bea first electrical node or a chip built in the first electrical node,and the data communication apparatus includes a processor 1102 and acommunications interface 1103. The processor 1102 is configured tocontrol and manage an action of the data communication apparatus. Forexample, the processor 1102 is configured to support the datacommunication apparatus in generating request information and parsingresponse information in the method embodiment, and/or performing anotherprocess of the technology described in this specification. In addition,the data communication apparatus may further include a memory 1101 and abus 1104. The processor 1102, the communications interface 1103, and thememory 1101 are connected to each other by bus 1104. The communicationsinterface 1103 is configured to support communication of the datacommunication apparatus. The memory 1101 is configured to store programcode and data of the data communication apparatus.

The processor 1102 may be a central processing unit, a general-purposeprocessor, a digital signal processor, an application-specificintegrated circuit, a field programmable gate array or anotherprogrammable logic device, a transistor logic device, a hardwarecomponent, or any combination thereof. The processor may implement orexecute various example logical blocks, modules, and circuits describedwith reference to content disclosed in this application. Alternatively,the processor may be a combination of processors implementing acomputing function, for example, a combination of one or moremicroprocessors, or a combination of the digital signal processor and amicroprocessor. The bus 1104 may be a peripheral component interconnect(Peripheral Component Interconnect, PCI) bus, an extended industrystandard architecture (Extended Industry Standard Architecture, EISA)bus, and or the like. The bus may be classified into an address bus, adata bus, a control bus, and the like. For ease of representation, onlyone thick line is used to represent the bus in FIG. 11, but this doesnot mean that there is only one bus or only one type of bus.

When an integrated unit is used, FIG. 12 is a possible schematicstructural diagram of a data communication apparatus used in theforegoing embodiment. The data communication apparatus may be a secondelectrical node or a chip built in the second electrical node, and thedata communication apparatus includes a receiving unit 1201 and asending unit 1202. The receiving unit 1201 is configured to support thedata communication apparatus in performing step 602, step 605, and/orstep 600 b in the method embodiment. The sending unit 1202 supports thedata communication apparatus in performing step 603 in the methodembodiment. Optionally, the data communication apparatus may furtherinclude a processing unit 1203, and the processing unit 1203 isconfigured to perform a step of parsing request information and/or astep of generating response information by the data communicationapparatus. All related content of the steps in the foregoing methodembodiment may be cited in function descriptions of correspondingfunction modules. Details are not described herein again.

Based on hardware implementation, the processing unit 1203 in thisapplication may be a processor of the data communication apparatus, thereceiving unit 1201 may be a receiver of the data communicationapparatus, and the sending unit 1202 may be a transmitter of the datacommunication apparatus. The transmitter and the receiver may be usuallyintegrated together to serve as a transceiver. Specifically, thetransceiver may also be referred to as a communications interface.

FIG. 13 is a schematic diagram of a possible logical structure of a datacommunication apparatus used in the foregoing embodiment provided in theembodiments of this application. The data communication apparatus may bea second electrical node or a chip built in the second electrical node,and the data communication apparatus includes a processor 1302 and acommunications interface 1303. The processor 1302 is configured tocontrol and manage an action of the data communication apparatus. Forexample, the processor 1302 is configured to support the datacommunication apparatus in parsing request information and generatingresponse information in the method embodiment, and/or performing anotherprocess of the technology described in this specification. In addition,the data communication apparatus may further include a memory 1301 and abus 1304. The processor 1302, the communications interface 1303, and thememory 1301 are connected to each other by bus 1304. The communicationsinterface 1303 is configured to support communication of the datacommunication apparatus. The memory 1301 is configured to store programcode and data of the data communication apparatus.

The processor 1302 may be a central processing unit, a general-purposeprocessor, a digital signal processor, an application-specificintegrated circuit, a field programmable gate array or anotherprogrammable logic device, a transistor logic device, a hardwarecomponent, or any combination thereof. The processor may implement orexecute various example logical blocks, modules, and circuits describedwith reference to content disclosed in this application. Alternatively,the processor may be a combination of processors implementing acomputing function, for example, a combination of one or moremicroprocessors, or a combination of the digital signal processor and amicroprocessor. The bus 1304 may be a peripheral component interconnect(PCI) bus, an extended industry standard architecture (EISA) bus, or thelike. The bus may be classified into an address bus, a data bus, acontrol bus, and the like. For ease of representation, only one thickline is used to represent the bus in FIG. 13, but this does not meanthat there is only one bus or only one type of bus.

When an integrated unit is used, FIG. 14 is a possible schematicstructural diagram of a data communication apparatus used in theforegoing embodiment. The data communication apparatus may be a thirdelectrical node or a chip built in the third electrical node, and thedata communication apparatus includes a receiving unit 1401 and asending unit 1402. The receiving unit 1401 is configured to support thedata communication apparatus in performing a step of receiving requestinformation sent by a first electrical node, a step of receivingresponse information sent by a second electrical node, and/or a step ofreceiving a first data packet sent in step 600 a in the methodembodiment. The sending unit 1402 supports the data communicationapparatus in performing a step of forwarding the request information tothe second electrical node, a step of sending the response informationto the first electrical node, a step of sending scheduling informationto at least one optical node, and/or a step of forwarding the first datapacket to the second electrical node in the method embodiment.Optionally, the data communication apparatus may further include aprocessing unit 1403, and the processing unit 1403 is configured toperform step 603 a, a step of parsing response information, and/or astep of generating scheduling information in the method embodiment thatare/is performed by the data communication apparatus. All relatedcontent of the steps in the foregoing method embodiment may be cited infunction descriptions of corresponding function modules. Details are notdescribed herein again.

Based on hardware implementation, the processing unit 1403 in thisapplication may be a processor of the data communication apparatus, thereceiving unit 1401 may be a receiver of the data communicationapparatus, and the sending unit 1402 may be a transmitter of the datacommunication apparatus. The transmitter and the receiver may be usuallyintegrated together to serve as a transceiver. Specifically, thetransceiver may also be referred to as a communications interface.

FIG. 15 is a schematic diagram of a possible logical structure of a datacommunication apparatus used in the foregoing embodiment provided in theembodiments of this application. The data communication apparatus may bea third electrical node or a chip built in the third electrical node,and the data communication apparatus includes a processor 1502 and acommunications interface 1503. The processor 1502 is configured tocontrol and manage an action of the data communication apparatus. Forexample, the processor 1502 is configured to support the datacommunication apparatus in performing step 603 a, parsing responseinformation, and generating scheduling information in the methodembodiment, and/or performing another process of the technologydescribed in this specification. In addition, the data communicationapparatus may further include a memory 1501 and a bus 1504. Theprocessor 1502, the communications interface 1503, and the memory 1501are connected to each other by bus 1504. The communications interface1503 is configured to support communication of the data communicationapparatus. The memory 1501 is configured to store program code and dataof the data communication apparatus.

The processor 1502 may be a central processing unit, a general purposeprocessor, a digital signal processor, an application-specificintegrated circuit, a field programmable gate array or anotherprogrammable logic device, a transistor logic device, a hardwarecomponent, or any combination thereof. The processor may implement orexecute various example logical blocks, modules, and circuits describedwith reference to content disclosed in this application. Alternatively,the processor may be a combination of processors implementing acomputing function, for example, a combination of one or moremicroprocessors, or a combination of the digital signal processor and amicroprocessor. The bus 1504 may be a peripheral component interconnect(PCI) bus, an extended industry standard architecture (EISA) bus, or thelike. The bus may be classified into an address bus, a data bus, acontrol bus, and the like. For ease of representation, only one thickline is used to represent the bus in FIG. 15, but this does not meanthat there is only one bus or only one type of bus.

In another embodiment of this application, a data communication systemis further provided. The data communication system is applied to a datacommunication network including at least two switching layers, where theat least two switching layers include a first layer and a second layer,the first layer includes a first electrical node and a second electricalnode, the second layer includes at least one optical node and a thirdelectrical node, and the first electrical node includes a first virtualoutput queue (VOQ). The first electrical node may be the firstelectrical node provided in the foregoing apparatus embodiments, and isconfigured to support the first electrical node in performing a step ofthe first electrical node in the method embodiment; and/or the secondelectrical node is the second electrical node provided in the foregoingapparatus embodiments, and is configured to support the secondelectrical node in performing a step of the second electrical node inthe method embodiment; and/or the third electrical node is the thirdelectrical node provided in the foregoing apparatus embodiments, and isconfigured to support the third electrical node in performing a step ofthe third electrical node in the method embodiment.

The first electrical node, the second electrical node, and the thirdelectrical node in the apparatus embodiments of this application maycorrespond to the first electrical node, the second electrical node, andthe third electrical node respectively in the method embodiment of thisapplication. In addition, modules and other operations and/or functionsof the first electrical node, the second electrical node, and the thirdelectrical node are used to implement corresponding procedures in theforegoing method embodiment. For brevity, descriptions of the methodembodiment of this application may be applicable to the apparatusembodiments, and details are not described herein again.

For beneficial effects of the apparatus embodiments in this application,refer to beneficial effects of the foregoing corresponding methodembodiment. Details are not described herein again. In addition, fordescriptions of related content of the apparatus embodiments of thisapplication, refer to the foregoing corresponding method embodiment.

A person of ordinary skill in the art may be aware that, in combinationwith the examples described in the embodiments disclosed in thisspecification, units and algorithm steps may be implemented byelectronic hardware or a combination of computer software and electronichardware. Whether the functions are performed by hardware or softwaredepends on particular applications and design constraint conditions ofthe technical solutions. A person skilled in the art may use differentmethods to implement the described functions for each particularapplication, but it should not be considered that the implementationgoes beyond the scope of this application.

It may be clearly understood by a person skilled in the art that, forthe purpose of convenient and brief description, for a detailed workingprocess of the foregoing system, apparatus, and unit, refer to acorresponding process in the foregoing method embodiment, and detailsare not described herein again.

In the several embodiments provided in this application, it should beunderstood that the disclosed system, apparatus, and method may beimplemented in other manners. For example, the described apparatusembodiment is merely an example. For example, the unit division ismerely logical function division and may be other division in actualimplementation. For example, a plurality of units or components may becombined or integrated into another system, or some features may beignored or not performed. In addition, the displayed or discussed mutualcouplings or direct couplings or communication connections may beimplemented through some interfaces. The indirect couplings orcommunication connections between the apparatuses or units may beimplemented in electronic, mechanical, or other forms.

The units described as separate parts may or may not be physicallyseparate, and parts displayed as units may or may not be physical units,may be located in one position, or may be distributed on a plurality ofnetwork units. Some or all of the units may be selected based on actualrequirements to achieve the objectives of the solutions of theembodiments.

In addition, functional units in the embodiments of this application maybe integrated into one processing unit, or each of the units may existalone physically, or two or more units are integrated into one unit.

When the functions are implemented in a form of a software functionalunit and sold or used as an independent product, the functions may bestored in a computer-readable storage medium. Based on such anunderstanding, the technical solutions of this application essentially,or the part contributing to the prior art, or some of the technicalsolutions may be implemented in a form of a software product. Thecomputer software product is stored in a storage medium, and includesseveral instructions for instructing a computer device (which may be apersonal computer, a server, or a network device) to perform all or someof the steps of the methods described in the embodiments of thisapplication.

In another embodiment of this application, a readable storage medium isfurther provided. The readable storage medium stores acomputer-executable instruction. When a device (which may be asingle-chip microcomputer, a chip, or the like) or a processor performssteps of the first electrical node in the data communication methodprovided in the foregoing method embodiment, the computer-executableinstruction in the readable storage medium is read. The foregoingreadable storage medium may include any medium that can store programcode, such as a USB flash drive, a removable hard disk, a read-onlymemory, a random access memory, a magnetic disk, or an optical disc.

In another embodiment of this application, a readable storage medium isfurther provided. The readable storage medium stores acomputer-executable instruction. When a device (which may be asingle-chip microcomputer, a chip, or the like) or a processor performssteps of the second electrical node in the data communication methodprovided in the foregoing method embodiment, the computer-executableinstruction in the readable storage medium is read. The foregoingreadable storage medium may include any medium that can store programcode, such as a USB flash drive, a removable hard disk, a read-onlymemory, a random access memory, a magnetic disk, or an optical disc.

In another embodiment of this application, a readable storage medium isfurther provided. The readable storage medium stores acomputer-executable instruction. When a device (which may be asingle-chip microcomputer, a chip, or the like) or a processor performssteps of the third electrical node in the data communication methodprovided in the foregoing method embodiment, the computer-executableinstruction in the readable storage medium is read. The foregoingreadable storage medium may include any medium that can store programcode, such as a USB flash drive, a removable hard disk, a read-onlymemory, a random access memory, a magnetic disk, or an optical disc.

In another embodiment of this application, a computer program product isfurther provided. The computer program product includes acomputer-executable instruction. The computer-executable instruction isstored in a computer-readable storage medium. At least one processor ofa device may read the computer-executable instruction from thecomputer-readable storage medium. The at least one processor executesthe computer-executable instruction to enable a device to perform a stepof the first electrical node in the data communication method providedin the foregoing method embodiment.

In another embodiment of this application, a computer program product isfurther provided. The computer program product includes acomputer-executable instruction. The computer-executable instruction isstored in a computer-readable storage medium. At least one processor ofa device may read the computer-executable instruction from thecomputer-readable storage medium. The at least one processor executesthe computer-executable instruction to enable a device to perform a stepof the second electrical node in the data communication method providedin the foregoing method embodiment.

In another embodiment of this application, a computer program product isfurther provided. The computer program product includes acomputer-executable instruction. The computer-executable instruction isstored in a computer-readable storage medium. At least one processor ofa device may read the computer-executable instruction from thecomputer-readable storage medium. The at least one processor executesthe computer-executable instruction to enable a device to perform a stepof the third electrical node in the data communication method providedin the foregoing method embodiment.

The foregoing descriptions are merely specific implementations of thisapplication, but are not intended to limit the protection scope of thisapplication. Any variation or replacement readily figured out by aperson skilled in the art within the technical scope disclosed in thisapplication shall fall within the protection scope of this application.Therefore, the protection scope of this application shall be subject tothe protection scope of the claims.

1. A data communication apparatus, wherein the data communicationapparatus serves as a first electrical node and is applied to a datacommunication network comprising at least two switching layers, the atleast two switching layers comprise a first layer and a second layer,the first layer comprises the first electrical node and a secondelectrical node, the second layer comprises at least one optical nodeand a third electrical node, and the first electrical node comprises afirst virtual output queue (VOQ); and the apparatus comprises: atransmitter, configured to send request information to the secondelectrical node, wherein the request information is used to request anexpected data volume quota of the first VOQ, and the first VOQ stores atleast one first data packet to be sent to the second electrical node;and a receiver, configured to receive response information, wherein theresponse information comprises a target data volume quota; wherein thetransmitter is further configured to send the at least one first datapacket to the second electrical node via the at least one optical nodebased on the target data volume quota.
 2. The apparatus according toclaim 1, wherein when there is a preset data volume quota for the firstVOQ, the transmitter is further configured to: send the at least onefirst data packet to the second electrical node via the third electricalnode based on the preset data volume quota.
 3. The apparatus accordingto claim 1, wherein at least one of the following occurs: the requestinformation comprises a request sequence number (SN), and a differencebetween the request SN and an initial SN indicates the expected datavolume quota; or the request information comprises a first value, andthe first value indicates the expected data volume quota; or theresponse information comprises a response SN, and a difference betweenthe response SN and the initial SN indicates the target data volumequota; or the response information comprises a second value, and thesecond value indicates the target data volume quota.
 4. The apparatusaccording to claim 1, wherein the response information further comprisesone of the following: an identifier of the first electrical node, anidentifier of the second electrical node, an identifier of the firstVOQ, an identifier of the at least one optical node, an identifier of asending path corresponding to the at least one optical node, a volumequota of data to be sent on the at least one optical node, or a sendingslot corresponding to the at least one optical node.
 5. The apparatusaccording to claim 1, wherein the transmitter is further configured to:send the request information to the second electrical node via the thirdelectrical node; or send a second data packet to the second electricalnode via one of the at least one optical node, wherein the second datapacket carries the request information.
 6. The apparatus according toclaim 1, wherein the receiver is further configured to: receive theresponse information sent by the second electrical node via the thirdelectrical node; or receive a third data packet sent by the secondelectrical node via one of the at least one optical node, wherein thethird data packet carries the response information.
 7. A datacommunication apparatus, wherein the data communication apparatus servesas a third electrical node and is applied to a data communicationnetwork comprising at least two switching layers, the at least twoswitching layers comprise a first layer and a second layer, the firstlayer comprises a first electrical node and a second electrical node,the second layer comprises at least one optical node and the thirdelectrical node, and the first electrical node comprises a first virtualoutput queue (VOQ); and the apparatus comprises: a receiver, configuredto receive request information sent by the first electrical node,wherein the request information is used to request an expected datavolume quota of the first VOQ, and the first VOQ stores at least onefirst data packet to be sent to the second electrical node; and atransmitter, configured to send the request information to the secondelectrical node; wherein the receiver is further configured to receiveresponse information sent by the second electrical node, wherein theresponse information comprises a target data volume quota; and thetransmitter is further configured to send the response information tothe first electrical node.
 8. The apparatus according to claim 7,wherein when there is a preset data volume quota for the first VOQ: thereceiver is further configured to receive the at least one first datapacket sent by the first electrical node based on the preset data volumequota; and the transmitter is further configured to send the at leastone first data packet to the second electrical node.
 9. The apparatusaccording to claim 7, wherein at least one of the following occurs: therequest information comprises a request sequence number (SN), and adifference between the request SN and an initial SN indicates theexpected data volume quota; or the request information comprises a firstvalue, and the first value indicates the expected data volume quota; orthe response information comprises a response SN, and a differencebetween the response SN and the initial SN indicates the target datavolume quota; or the response information comprises a second value, andthe second value indicates the target data volume quota.
 10. Theapparatus according to claim 7, wherein the apparatus further comprises:a non-transitory memory storage comprising instructions; and one or morehardware processors in communication with the non-transitory memorystorage, wherein the one or more hardware processors execute theinstructions to: determine, based on the target data volume quota, avolume quota of data to be sent on each of the at least one opticalnode; wherein correspondingly, the response information furthercomprises one of the following: an identifier of the first electricalnode, an identifier of the second electrical node, an identifier of thefirst VOQ, an identifier of the at least one optical node, an identifierof a sending path corresponding to the at least one optical node, avolume quota of data to be sent on the at least one optical node, or asending slot corresponding to the at least one optical node.
 11. Theapparatus according to claim 10, wherein the transmitter is furtherconfigured to: send scheduling information to each of the at least oneoptical node, wherein the scheduling information comprises at least oneof the following information: the identifier of the first electricalnode, the identifier of the second electrical node, the identifier ofthe first VOQ, an identifier of a sending path corresponding to theoptical node, a volume quota of data to be sent on the optical node, ora sending slot corresponding to the optical node.
 12. A datacommunication apparatus, wherein the data communication apparatus servesas a second electrical node and is applied to a data communicationnetwork comprising at least two switching layers, the at least twoswitching layers comprise a first layer and a second layer, the firstlayer comprises a first electrical node and the second electrical node,the second layer comprises at least one optical node and a thirdelectrical node, and the first electrical node comprises a first virtualoutput queue (VOQ); and the apparatus comprises: a receiver, configuredto receive request information, wherein the request information is usedto request an expected data volume quota of the first VOQ, and the firstVOQ stores at least one first data packet to be sent to the secondelectrical node; and a transmitter, configured to send responseinformation, wherein the response information comprises a target datavolume quota; wherein the receiver is further configured to receive theat least one first data packet that is sent by the first electrical nodevia the at least one optical node based on the target data volume quota.13. The apparatus according to claim 12, wherein when there is a presetdata volume quota for the first VOQ, the receiver is further configuredto: receive the at least one first data packet that is sent by the firstelectrical node to the second electrical node via the third electricalnode based on the preset data volume quota.
 14. The apparatus accordingto claim 12, wherein at least one of the following occurs: the requestinformation comprises a request sequence number (SN), and a differencebetween the request SN and an initial SN indicates the expected datavolume quota; or the request information comprises a first value, andthe first value indicates the expected data volume quota; or theresponse information comprises a response SN, and a difference betweenthe response SN and the initial SN indicates the target data volumequota; or the response information comprises a second value, and thesecond value indicates the target data volume quota.
 15. The apparatusaccording to claim 12, wherein the receiver is further configured to:receive, via the third electrical node, the request information sent bythe first electrical node; or receive, via one of the at least oneoptical node, a second data packet sent by the first electrical node,wherein the second data packet carries the request information.
 16. Theapparatus according to claim 12, wherein the transmitter is furtherconfigured to: send the response information to the first electricalnode via the third electrical node; or send a third data packet to thefirst electrical node via one of the at least one optical node, whereinthe third data packet carries the response information.